Vehicle headrests are conventionally mounted on one or two support posts that are inserted into guide sleeves, tubes or brackets affixed to the seat back frame structure. Generally, some sort of adjustment mechanism is provided to enable variable vertical positioning of the headrest and to prevent inadvertent removal of the headrest from the seatback.
Modern vehicle seat frame structures are made of metal tubing. Headrest guide sleeves are conventionally mounted on a bracket on the seat back frame tubing. Such a guide is shown in U.S. Pat. No. 4,577,904 to Wiese et al. which includes a plastic sleeve that is bayonet mounted to a bracket, a formed flat metal spring for detenting in headrest support post notches, and a release button.
Another arrangement utilizes holes drilled through the tubing to provide metal collars which cooperate with a two-piece plastic guide to provide the headrest support post guide. One guide piece is installed before the seat back is trimmed with upholstery and a cooperating plastic guide socket is installed after seat trimming to finish off the hole in the upholstery. This arrangement is disclosed in U.S. Pat. No. 4,679,850 to Bianchi et al.
Both of the above described arrangements require either a special bracket on the seat back frame structure or a multi-part guide that is installed in two steps.